


What Actually Happens When You Fuck Sans

by Mariiii



Category: Undertale (Video Game)
Genre: Collar/leash, Degradation, Dom Sans, F/M, Fingering, Master/Pet, Mutual Masturbation, NSFW, Petplay, Reader is sub, Sexual Dysfunction, Smut, anal mention, but canon, but it doesn't actually happen, ecto dick, it's good just read it ok, noncon, ok it's consensual but it's also kinda not, reader does not orgasm, reader has sexual dysfunction teehee, reader is female, sans is really selfish and rude, sans x reader, shy reader, this story is plot heavy but skippable, um
Language: English
Status: Completed
Published: 2020-07-02
Updated: 2020-07-02
Packaged: 2021-03-04 23:28:34
Rating: Explicit
Warnings: Rape/Non-Con
Chapters: 1
Words: 2,040
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25024702
Author URL: https://archiveofourown.org/users/Mariiii/pseuds/Mariiii
Summary: You make a mistake and Sans decides to completely obliterate you for it
Relationships: Sans (Undertale)/Reader
Comments: 22
Kudos: 93





	What Actually Happens When You Fuck Sans

**Author's Note:**

> thank u to ari for giving me the majority of the plot for this :-) 
> 
> the tags sound so fucking cringe ok but hear me out. if you like the way sans acts IN CANON then you have come to the right place. just b mindful of the tags
> 
> the end gets fucking personal oopsie :3c but im proud of it so here u go. hope maybe one person in this universe can enjoy what i've made here. PLS COMMENT IF U ENJOYED IT OR HAVE SMTH TO SAY OR YELL AT ME @SANSYSGF ON TUMBLR THANKUUUU ❤️❤️❤️

You knew you were in trouble the second the words came out of your mouth. 

There was no big reaction; not even a flinch (not that you had expected one), but you knew Sans well enough to know when you had struck a nerve. 

Everyone has their individual boundaries.   
Sans was very laid back, but even he had lines that those close to him knew not to cross, including some that were particularly unspoken between the two of you.

The part where you made a mistake was in the assumption that you were close enough to him to break those rules. 

"He's an adult, Sans. You don't need to censor everything from him."

You knew it would be a risky statement, but you and Sans had grown very close. He needed to be told that he was being overbearing. Surely he would appreciate your honesty?

Reading Sans' expressions is a learned skill, considering that he has very little of them. He's always smiling. Even after the words left your mouth, the tight grin remained. His eyelights simply shrunk, and his stare felt like it bore into your soul.

"...don't tell me how to take care of my brother, kay?" 

As someone who's extremely averse to criticism, you sure were dating someone pretty blunt.

Then, like you'd never said anything, his lazy "expression" returned. 

"anyway. can't believe you managed to pull me away from my work for this long." He pats your shoulder, winking. "thanks for the chat, pal."

Just like that, he vanished into thin air.

...He didn't even use a pet name. It was like he was speaking to an acquaintance, not his girlfriend. It left a pit of guilt in your stomach.

It took you about three minutes to come to your senses about the whole ordeal. Why did you feel guilty? He was the one being overdramatic and controlling! You said what needed to be said. 

Apparently, Sans didn't feel the same way.  
You didn't see him at all that night or the day after, which left you and your brain to replay and mull over the conversation until you were sick of it. He disappeared often, but it still made you anxious. It wasn't until the next evening that you heard him talking to Papyrus downstairs and you knew he was home.

You heard his footsteps coming up the stairs and nervously curled up in his sheets as the door slowly unlocked and opened. 

The light from the hallway disappeared as the door clicked shut, but his gaze managed to catch yours. 

"Where have you been?" You ask quietly, sitting up. You can hear him kicking off his shoes and tossing his jacket on the floor. 

"work." He answers calmly. "did i wake ya?" 

"No." You can't see anything, but the sound of clothes shuffling tells you he's probably changing out of his uniform. The silence starts to stretch out. It's unbearable. 

"Sans, I'm sorry about what I said the other day. I didn't mean to upset you. I just thought that it was worth saying at some point in time, I didn't think it would be that serious." The apology spills before you can stop yourself. You don't care if he's technically in the wrong anymore, you just want him to like you again.

His prolonged silence makes you want to scream. 

"Y-You know I wouldn't be saying it unless I just wanted Papyrus to be happy!" You plead. 

Oops, probably shouldn't have said that either. If you were fucked before, you were definitely fucked now.

"...you're a real chatterbox lately, arentcha?" His tone is akin to a drawl. It makes you shiver; that was just rude.

"What?" You reply shakily. You hear him walk towards the front of the bed, and you can slightly make out his figure standing in front of you.

"if ya know what's best for my brother, you could always just take the reins. it'd make my job a lot easier."

"I didn't mean it like that!" You backpedal, mentally kicking yourself. All you want is for this to be over.

"ya sure? cause you know how much i love doing nothing." You can hear how smug he is.

You purse your lips in frustration. You can't possibly understand what was so wrong about what you said. It just doesn't make sense!

He chuckles lowly, causing your gaze to quickly flit back to his face. What is he laughing about?!

"y'know, it's kinda impolite to critique someone on their parenting." He pauses. "or, heh, brothering." He suddenly turns and walks away. You hear the sound of a drawer opening and some more shuffling around.

"never thought i'd need to use this." He mutters under his breath, just loud enough to where you can make out the words. The pit in your stomach grows impossibly deeper. Oh no.

"guess you aren't properly trained after all, huh?" He approaches the foot of the bed once more, shuffling in his pockets. You hear the sound of metal clinking together, along with your heartbeat in your ears.

"take your clothes off." 

The blunt command sent a wave of heat into your abdomen. Your primal instincts told you to just obey and don't say a word. 

This was so much easier than confrontation or communication. You liked being treated like this. You needed to be put in your place. It was familiar, and it meant you didn't have to be in charge of anything. So you did what you were told and you did it gladly.

You had to stand to get fully undressed, so now you were much taller than him, feeling very exposed and uncomfortable. 

You hoped he would at least praise you, but he didn't. He wordlessly took out your collar and gently fastened it to your neck.

"really didn't think i needed to teach you proper manners." He clips a leash to your collar, checking it's stability with a harsh tug. You lurch forwards, letting out a squeak of surprise as his face presses against your neck.

"get on your knees." Your eyes flutter as he growls into your neck and you immediately fall to the ground. 

You didn't know he even had a leash, let alone would be this rough with you. He's never harsh like this. You're scared, but you're also shamefully wet and shaking at the sight of his cock protruding in his shorts. 

"...heh. you really are a slut, arentcha?" 

You have to suppress a moan as your breathing picks up. He's right; you're pathetic. The fact that you want to do this, that you're actively fighting the urge to rub your face against his bulge and beg to suck him off without him even asking you. It's absolutely disgusting.

"...did you just moan?" He pauses, then laughs. The feeling you get in your stomach is the epitome of shame. He's literally laughing at you. 

"wow. that's hilarious...y'know, i've changed my mind. if you're that much of a whore, giving you my cock isn't exactly a punishment, is it?" He muses, almost purring.

He gives your leash another harsh tug, shoving his dick in your face. An involuntary whimper slips from your throat, and he chuckles loudly.

"be a good whore and bend over." 

Releasing the pressure on your leash causes you to jerk backwards a bit. You hurry to present yourself to him, despite your confusion on how this is any worse of a punishment for you. You just hope he doesn't notice the wetness dripping from your cunt.

That's not what he comments on, to your surprise...No, to your complete horror.

"i was thinking..." His phalanges find your hips as he fits himself against you. 

"since you love my cock so much, how bout i fuck ya someplace beyond your wildest asspectations." He laughs while you cringe at the godawful pun. That is, until you realize what he just suggested. 

"...No, no, Sans, you're not serious!" You plead, ignoring your previous vow of silence. Moments later you feel him rubbing himself against your ass, teasingly rocking his hips. There's no way he's actually going to do this to you...right? You're terrified. 

"Sans, don't..."

In the midst of feeling completely objectified, you can't help but start to bargain with yourself. Maybe it's not so bad...at least you're pleasing him. At least it's a proper punishment for the awful things you said...you made him angry and you should have to pay for it. You're willing to pay for it if it will make him love you again.

Your pleas gradually turn to whimpers, then to moans. It only took him moments to make you want something you hated with every fiber of your being. He starts to push the head in and you have to cover your mouth to stop from begging him.

"holy shit, you're a freak." He stops, causing you to whine pathetically. "i just can't humiliate you enough, can i?"

Now is the best time for you to probably just shut up.

"...quiet now, hm?" He pauses, giving you a moment to breathe. "get up and lay back."

You shakily do as he says, turning to face him and settling yourself against the pillows. He scoots closer to you in the meantime. You can't bring yourself to look him in the eye. Instead, your gaze flits from the hand clutched around your leash to his cock, which was now freed from his shorts, hoping to god he had some relief planned for you.

"spread your legs. i wanna see that pretty cunt since i won't get to fuck it." You obey in utter terror at his words. What is he going to do now?

"now finger yourself." 

You open your mouth to protest. 

"shut up and do it." He snaps, almost growling. You slide a finger in your soaked cunt, crying out at just the slightest bit of attention after being teased for so long. Right after that initial feeling, it gradually fades into nothing but a pleasureless function. You hate this. After all that you've confided in him, he's using one of your deepest insecurities to make you feel like shit.

"better look at me." He warns, wrapping a hand around himself and slowly stroking up and down. You're forced to watch as he jerks off to the image of you being unable to satisfy yourself. He knows how this feels to you, and he knows you can't come. As hard as you try, the only pleasure you're getting is from watching him please himself. If you're pleasing him, you can feel good.

He picks up the pace, his deep groans joining your desperate pleas to be satisfied.

"fuck...i wanna feel you so bad. wanna feel your tight little cunt." He moans low in his throat, squeezing his cock as precum drips down his hand.

"it's too bad you've been a dirty bitch. now we both don't get what we want. y'know--fuck--y-you really gotta learn where you stand. been such a brat lately."

"I'm sorry! Sans, please..."

"c'mon, you can do better than that. beg like the whore you are."

"Sans please, i need you! i need you to make me come i need to be filled i'll take it wherever you want i need it sans please--"

He blew his load right in your face. 

You let out a pathetic whine, eyes screwing shut. There's a growl low in his throat as he works himself through his orgasm, cum spurting onto your face. It drips down your nose and mouth but you don't dare wipe it off out of fear.

You manage to open one eye and squint as you watch his cock dissipate and he gets up out of bed. Is he...going to leave?

"Sans..." You whimper.

"heh. thanks for treating me." He catches your glance, winking. He's putting on his jacket.

"you don't look so good. maybe next time you'll learn not to say stupid shit."

"Please don't leave." He's not serious. It's just another joke, right?

He opens the door to leave. You might cry.

"love you, angel." He whispers, then the door clicks shut. You hear his footsteps disappear down the hall.

...Let's just say you've learned your lesson.


End file.
